Emulator Trainer Question

This might seem stupid but I must ask it. Does anybody know how do they make game trainers?? (i.e. programs that change the way a game is working. They are used while a game is running) Actually I badly need to create a trainer for neorageX but I do not know even the basics. There are two 'dipswitches' that I need to change. The emulator (neorageX) uses constant addresses in memory for its variables that I need to change (means I need to change the value of variables not their addresses). Now this may look ridiculous but I do not know the address of the two variables that I need to change! So if anybody knows how to make a neorageX trainer, please tell me.

1. Given the requirements I'm not sure Visual Basic would be my language of choice.

2. If you don't know the variables you need to change, how would you expect to change them?